Conventional portable electronic or magnetic devices are used for many different applications. Such portable devices can be for example access devices such as keycards, identification devices, or credit or debit devices such as the so-called smart cards.
Electronic identification devices are widely used by banks, credit companies, stores, to allow automated monetary transactions without the assistance of a bank teller.
For conventional credit cards, a magnetic strip is encoded with a small amount of coded information identifying the cardholder, such as an identification code and a personal identification number (PIN). To access the information held by such cards after or during a transaction, a suitable transaction interface machine comprising an appropriate magnetic card reader is required. Transaction or other account-related information can be outputted on a display screen located on the transaction machine.
Some prior art identification or transaction cards incorporate greater storage capacity and data processing means in the form of a microchip carried by the plastic main body of a smart card. These smart cards can store more data than standard magnetic cards. These cards, however, still require the use of a card reader interface machine to access the information comprised thereon, and a supplementary screen on the interface machine is required to view their content.
Some prior art identification cards have been provided with an in-built display screen and an information decoder cooperating with each other to access, decode and visualize coded information comprised in a memory unit located on the card. These prior art devices, however, necessitate multiple controls thereon to accomplish different functions of the card.